Commit a2601e2b authored by Petr Machata's avatar Petr Machata Committed by David S. Miller
Browse files

nexthop: Add netlink handlers for resilient nexthop groups 



Implement the netlink messages that allow creation and dumping of resilient
nexthop groups.

Signed-off-by: default avatarPetr Machata <petrm@nvidia.com>
Reviewed-by: default avatarIdo Schimmel <idosch@nvidia.com>
Reviewed-by: default avatarDavid Ahern <dsahern@kernel.org>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent cfc15c1d

net/ipv4/nexthop.c

+145 −5
Original line number Diff line number Diff line
@@ -16,6 +16,9 @@ 
#include <net/route.h>

#include <net/sock.h>



#define NH_RES_DEFAULT_IDLE_TIMER	(120 * HZ)

#define NH_RES_DEFAULT_UNBALANCED_TIMER	0	/* No forced rebalancing. */



static void remove_nexthop(struct net *net, struct nexthop *nh,

			   struct nl_info *nlinfo);
@@ -32,6 +35,7 @@ static const struct nla_policy rtm_nh_policy_new[] = { 
	[NHA_ENCAP_TYPE]	= { .type = NLA_U16 },

	[NHA_ENCAP]		= { .type = NLA_NESTED },

	[NHA_FDB]		= { .type = NLA_FLAG },

	[NHA_RES_GROUP]		= { .type = NLA_NESTED },

};



static const struct nla_policy rtm_nh_policy_get[] = {
@@ -45,6 +49,12 @@ static const struct nla_policy rtm_nh_policy_dump[] = { 
	[NHA_FDB]		= { .type = NLA_FLAG },

};



static const struct nla_policy rtm_nh_res_policy_new[] = {

	[NHA_RES_GROUP_BUCKETS]			= { .type = NLA_U16 },

	[NHA_RES_GROUP_IDLE_TIMER]		= { .type = NLA_U32 },

	[NHA_RES_GROUP_UNBALANCED_TIMER]	= { .type = NLA_U32 },

};



static bool nexthop_notifiers_is_empty(struct net *net)

{

	return !net->nexthop.notifier_chain.head;
@@ -588,6 +598,41 @@ static void nh_res_time_set_deadline(unsigned long next_time, 
		*deadline = next_time;

}



static clock_t nh_res_table_unbalanced_time(struct nh_res_table *res_table)

{

	if (list_empty(&res_table->uw_nh_entries))

		return 0;

	return jiffies_delta_to_clock_t(jiffies - res_table->unbalanced_since);

}



static int nla_put_nh_group_res(struct sk_buff *skb, struct nh_group *nhg)

{

	struct nh_res_table *res_table = rtnl_dereference(nhg->res_table);

	struct nlattr *nest;



	nest = nla_nest_start(skb, NHA_RES_GROUP);

	if (!nest)

		return -EMSGSIZE;



	if (nla_put_u16(skb, NHA_RES_GROUP_BUCKETS,

			res_table->num_nh_buckets) ||

	    nla_put_u32(skb, NHA_RES_GROUP_IDLE_TIMER,

			jiffies_to_clock_t(res_table->idle_timer)) ||

	    nla_put_u32(skb, NHA_RES_GROUP_UNBALANCED_TIMER,

			jiffies_to_clock_t(res_table->unbalanced_timer)) ||

	    nla_put_u64_64bit(skb, NHA_RES_GROUP_UNBALANCED_TIME,

			      nh_res_table_unbalanced_time(res_table),

			      NHA_RES_GROUP_PAD))

		goto nla_put_failure;



	nla_nest_end(skb, nest);

	return 0;



nla_put_failure:

	nla_nest_cancel(skb, nest);

	return -EMSGSIZE;

}



static int nla_put_nh_group(struct sk_buff *skb, struct nh_group *nhg)

{

	struct nexthop_grp *p;
@@ -598,6 +643,8 @@ static int nla_put_nh_group(struct sk_buff *skb, struct nh_group *nhg) 


	if (nhg->mpath)

		group_type = NEXTHOP_GRP_TYPE_MPATH;

	else if (nhg->resilient)

		group_type = NEXTHOP_GRP_TYPE_RES;



	if (nla_put_u16(skb, NHA_GROUP_TYPE, group_type))

		goto nla_put_failure;
@@ -613,6 +660,9 @@ static int nla_put_nh_group(struct sk_buff *skb, struct nh_group *nhg) 
		p += 1;

	}



	if (nhg->resilient && nla_put_nh_group_res(skb, nhg))

		goto nla_put_failure;



	return 0;



nla_put_failure:
@@ -700,13 +750,26 @@ static int nh_fill_node(struct sk_buff *skb, struct nexthop *nh, 
	return -EMSGSIZE;

}



static size_t nh_nlmsg_size_grp_res(struct nh_group *nhg)

{

	return nla_total_size(0) +	/* NHA_RES_GROUP */

		nla_total_size(2) +	/* NHA_RES_GROUP_BUCKETS */

		nla_total_size(4) +	/* NHA_RES_GROUP_IDLE_TIMER */

		nla_total_size(4) +	/* NHA_RES_GROUP_UNBALANCED_TIMER */

		nla_total_size_64bit(8);/* NHA_RES_GROUP_UNBALANCED_TIME */

}



static size_t nh_nlmsg_size_grp(struct nexthop *nh)

{

	struct nh_group *nhg = rtnl_dereference(nh->nh_grp);

	size_t sz = sizeof(struct nexthop_grp) * nhg->num_nh;



	return nla_total_size(sz) +

	size_t tot = nla_total_size(sz) +

		nla_total_size(2); /* NHA_GROUP_TYPE */



	if (nhg->resilient)

		tot += nh_nlmsg_size_grp_res(nhg);



	return tot;

}



static size_t nh_nlmsg_size_single(struct nexthop *nh)
@@ -876,7 +939,7 @@ static int nh_check_attr_fdb_group(struct nexthop *nh, u8 *nh_family, 


static int nh_check_attr_group(struct net *net,

			       struct nlattr *tb[], size_t tb_size,

			       struct netlink_ext_ack *extack)

			       u16 nh_grp_type, struct netlink_ext_ack *extack)

{

	unsigned int len = nla_len(tb[NHA_GROUP]);

	u8 nh_family = AF_UNSPEC;
@@ -937,8 +1000,14 @@ static int nh_check_attr_group(struct net *net, 
	for (i = NHA_GROUP_TYPE + 1; i < tb_size; ++i) {

		if (!tb[i])

			continue;

		if (i == NHA_FDB)

		switch (i) {

		case NHA_FDB:

			continue;

		case NHA_RES_GROUP:

			if (nh_grp_type == NEXTHOP_GRP_TYPE_RES)

				continue;

			break;

		}

		NL_SET_ERR_MSG(extack,

			       "No other attributes can be set in nexthop groups");

		return -EINVAL;
@@ -2475,6 +2544,70 @@ static struct nexthop *nexthop_add(struct net *net, struct nh_config *cfg, 
	return nh;

}



static int rtm_nh_get_timer(struct nlattr *attr, unsigned long fallback,

			    unsigned long *timer_p, bool *has_p,

			    struct netlink_ext_ack *extack)

{

	unsigned long timer;

	u32 value;



	if (!attr) {

		*timer_p = fallback;

		*has_p = false;

		return 0;

	}



	value = nla_get_u32(attr);

	timer = clock_t_to_jiffies(value);

	if (timer == ~0UL) {

		NL_SET_ERR_MSG(extack, "Timer value too large");

		return -EINVAL;

	}



	*timer_p = timer;

	*has_p = true;

	return 0;

}



static int rtm_to_nh_config_grp_res(struct nlattr *res, struct nh_config *cfg,

				    struct netlink_ext_ack *extack)

{

	struct nlattr *tb[ARRAY_SIZE(rtm_nh_res_policy_new)] = {};

	int err;



	if (res) {

		err = nla_parse_nested(tb,

				       ARRAY_SIZE(rtm_nh_res_policy_new) - 1,

				       res, rtm_nh_res_policy_new, extack);

		if (err < 0)

			return err;

	}



	if (tb[NHA_RES_GROUP_BUCKETS]) {

		cfg->nh_grp_res_num_buckets =

			nla_get_u16(tb[NHA_RES_GROUP_BUCKETS]);

		cfg->nh_grp_res_has_num_buckets = true;

		if (!cfg->nh_grp_res_num_buckets) {

			NL_SET_ERR_MSG(extack, "Number of buckets needs to be non-0");

			return -EINVAL;

		}

	}



	err = rtm_nh_get_timer(tb[NHA_RES_GROUP_IDLE_TIMER],

			       NH_RES_DEFAULT_IDLE_TIMER,

			       &cfg->nh_grp_res_idle_timer,

			       &cfg->nh_grp_res_has_idle_timer,

			       extack);

	if (err)

		return err;



	return rtm_nh_get_timer(tb[NHA_RES_GROUP_UNBALANCED_TIMER],

				NH_RES_DEFAULT_UNBALANCED_TIMER,

				&cfg->nh_grp_res_unbalanced_timer,

				&cfg->nh_grp_res_has_unbalanced_timer,

				extack);

}



static int rtm_to_nh_config(struct net *net, struct sk_buff *skb,

			    struct nlmsghdr *nlh, struct nh_config *cfg,

			    struct netlink_ext_ack *extack)
@@ -2553,7 +2686,14 @@ static int rtm_to_nh_config(struct net *net, struct sk_buff *skb, 
			NL_SET_ERR_MSG(extack, "Invalid group type");

			goto out;

		}

		err = nh_check_attr_group(net, tb, ARRAY_SIZE(tb), extack);

		err = nh_check_attr_group(net, tb, ARRAY_SIZE(tb),

					  cfg->nh_grp_type, extack);

		if (err)

			goto out;



		if (cfg->nh_grp_type == NEXTHOP_GRP_TYPE_RES)

			err = rtm_to_nh_config_grp_res(tb[NHA_RES_GROUP],

						       cfg, extack);



		/* no other attributes should be set */

		goto out;